Definition of ransomware

: malware that requires the victim to pay a ransom to access encrypted files

In September of 2013, security for small accounting offices changed forever with the appearance of a new class of threats called ransomware. … you open a file attached to an innocent-looking e-mail, and the program encrypts key files and drives so they cannot be accessed. The files are locked until you pay a ransom.

—Dave Mcclure

With ransomware, a hacker slips into a system, then puts encryption controls in place that locks users out. The hackers then demand money to "unlock" the data.

—Elizabeth Millard

Today's ransomware scammers often demand payment in bitcoin because the digital currency is easy to use, fast and provides a heightened anonymity for the scammers, according to the FBI warning.

The second was directed at North Korea and deals with a large-scale ransomware attack that exploited a software vulnerability in Microsoft Windows to shut down hospitals, banks, and railroads all over the world.

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